404 / 2019-02-28 19:20:42

Initial Decomposition of the Co-crystal of TNT/CL-20: Sensitivity Decrease under Shock Loading

CL-20/TNT,shock wave,decomposition mechanism

全体主题 > Fundamental Physics at Extremes

Co-crystal of CL-20/TNT is a low-sensitive and high-energetic explosive by combining CL-20 and TNT molecules by the co-crystallization technique recently. However, the underlying properties and decay mechanism remain unclear. In this work, we performed quantum based multiscale shock simulation under shock loading by self-consistent charge density-functional tight binding method to study the initial chemical mechanism of CL-20/TNT. The results the initial decomposition steps of the co-crystal are consistent with that of components, N-NO2 bond cleavage at low velocity is observed while is inhibited at high velocity for CL-20 molecule, H transfer and C-NO2 bond break of TNT molecule are main initial decay step. Meanwhile, CL-20 decomposes faster than TNT and the releasing heat of CL-20 decomposition are transferred to TNT to increase decomposition rate of TNT during the shock decomposition. Moreover, the evolution of main stable products strongly depends on the shock strength. NO2 is the dominant primary intermediates resulting from weak bond barrier, and these products such as CO, N2 and NO are the main products determined by the shock strength. This study makes new insights into the initial decomposition mechanism of CL-20/TNT upon shock loading at the atomistic level, and has important implications for understanding and development of energetic materials.